Mineral Like (Natural Glass)

Diamond

Carbon (C)

Quartz (specifically Clear and Rose Quartz)

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (Fe-rich)

Halite

Halite (NaCl)

Botryoidal Chalcedony (likely Desert Rose/Agatized Geode Crust)

Silicon Dioxide (SiO2)

Blue Sapphire (in a faceted jewelry setting)

Corundum (Al2O3) with trace Iron and Titanium

Corundum

Corundum (Aluminium oxide, Al2O3)

Rose Quartz

Silicon Dioxide (SiO2) with trace impurities of titanium, iron, or manganese

Sandstone (lithic/greywacke variant)

Clastic sedimentary rock (primarily SiO2 with rock fragments)

Quartz

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2) with trace Titanium, Manganese, or Iron

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Jasper Pendant

Chalcedony (Quartz) - SiO2

Obsidian with Spherulitic Devitrification (Snowflake Obsidian/Mahogany related)

Volcanic Glass (70% or more SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Heat-Treated Citrine (Amethyst-based)

Quartz (Silicon Dioxide) - SiO2

Limonite (Iron Ore Congcretion)

Limonite (a mixture of hydrated iron(III) oxide-hydroxides, FeO(OH)·nH2O)

Fluorite (Green Fluorite)

Fluorite (Calcium Fluoride, CaF2)

Cloudy Quartz

Silicon Dioxide (SiO2)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz Crystal (specifically Rock Crystal)

Silicon Dioxide (SiO2)

Sandstone

Arenite

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Quartz / Common Opal Transition

Silicon Dioxide (SiO2)

Sandstone (likely Quartz Sandstone)

Arenite (composed primarily of SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Orthoclase Feldspar

Orthoclase (KAlSi3O8)

Clear Quartz

Silicon Dioxide (SiO2)

Diamond

Diamond (C)

Granite

Granite (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite mica

Quartz Geode or Druzy Quartz in Host Rock

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Granite (Background) and Quartzite/River Pebble (Foreground Heart)

Phaneritic Felsic Igneous Rock (Granite background)

Green Aventurine

Aventurine Quartz (SiO2 + Fuchsite mica)

Quartz (Smoky/Clear variety)

Silicon Dioxide (SiO2)

Quartz Vein in Host Rock (Gossanous Matrtix)

Silicon Dioxide (SiO2) with iron oxides (Limonite/Hematite)

Mahogany Obsidian

Volcanic Glass (with inclusions of Magnetite or Hematite)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)